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Risk adjustment is needed to fairly compare central-line–associated bloodstream infection (CLABSI) rates between hospitals. Until 2017, the Centers for Disease Control and Prevention (CDC) methodology adjusted CLABSI rates only by type of intensive care unit (ICU). The 2017 CDC models also adjust for hospital size and medical school affiliation. We hypothesized that risk adjustment would be improved by including patient demographics and comorbidities from electronically available hospital discharge codes.

METHODS

Using a cohort design across 22 hospitals, we analyzed data from ICU patients admitted between January 2012 and December 2013. Demographics and International Classification of Diseases, Ninth Edition, Clinical Modification (ICD-9-CM) discharge codes were obtained for each patient, and CLABSIs were identified by trained infection preventionists. Models adjusting only for ICU type and for ICU type plus patient case mix were built and compared using discrimination and standardized infection ratio (SIR). Hospitals were ranked by SIR for each model to examine and compare the changes in rank.

RESULTS

Overall, 85,849 ICU patients were analyzed and 162 (0.2%) developed CLABSI. The significant variables added to the ICU model were coagulopathy, paralysis, renal failure, malnutrition, and age. The C statistics were 0.55 (95% CI, 0.51–0.59) for the ICU-type model and 0.64 (95% CI, 0.60–0.69) for the ICU-type plus patient case-mix model. When the hospitals were ranked by adjusted SIRs, 10 hospitals (45%) changed rank when comorbidity was added to the ICU-type model.

CONCLUSIONS

Our risk-adjustment model for CLABSI using electronically available comorbidities demonstrated better discrimination than did the CDC model. The CDC should strongly consider comorbidity-based risk adjustment to more accurately compare CLABSI rates across hospitals.

The age of sand dunes in the Nebraska Sand Hills has been controversial, with some investigators suggesting a full-glacial age and others suggesting that they were last active in the late Holocene. New accelerator mass spectrometry radiocarbon ages of unaltered bison bones and organic-rich sediments suggest that eolian sand deposition occurred at least twice in the past 3000 14C yr B.P. in three widely separated localities and as many as three times in the past 800 14C yr at three other localities. These late Holocene episodes of eolian activity are probably the result of droughts more intense than the 1930s “Dust Bowl” period, based on independent Great Plains climate records from lake sediments and tree rings. However, new geochemical data indicate that the Nebraska Sand Hills are mineralogically mature. Eolian sands in Nebraska have lower K-feldspar (and K2O, Rb, and Ba) contents than most possible source sediments and lower K-feldspar contents than dunes of similar age in Colorado. The most likely explanation for mineralogical maturity is reduction of sand-sized K-feldspar to silt-sized particles via ballistic impacts due to strong winds over many cycles of eolian activity. Therefore, dunes of the Nebraska Sand Hills must have had a long history, probably extending over more than one glacial–interglacial cycle, and the potential for reactivation is high, with or without a future greenhouse warming.

This is the official guideline endorsed by the surgical specialty associations involved in the care of head and neck cancer patients in the UK. This paper summarises the current state of play in the organisation and provision of head and neck cancer surgical services in the UK.

The transition from Palaeoindian to Archaic societies in North America is often viewed as a linear progression over a brief but time-transgressive period. New evidence from the Wilson-Leonard site in Texas suggests social experimentation by Palaeoindians over a 2500-year period eventually resulted in Archaic societies. The process was neither short nor linear, and the evidence shows that different but contemporaneous lifeways existed in a variety of locales in the south-central US in the Early Holocene.

Purpose: Need for reliable, thermally stable Ohmic metallizations for ZnO. Because of difficulties with current common contact metals, there exists a heavy desire for metals with high melting temperatures and low reactivities.

The development of new etching and contact metallurgies for the ZnO/ZnMgO/ZnCdO materials system and various approaches for realizing ZnO LEDs are reviewed. ZnO nanorod MOSFETs and pH sensors have been demonstrated. In addition, selective detection of hydrogen with Pt-coated single ZnO nanorods is discussed discussed. The Pt-coated single nanorods show a current response approximately a factor of three larger at room temperature upon exposure to 500ppm H2 in N2 than thin films of ZnO. The power consumption of these sensors can be very small (in the nW range) when using discontinuous coatings of Pt. Once the Pt coating becomes continuous, the current required to operate the sensors increases to the μW range. The ZnO nanorods are insensitive to oxygen in the measurement ambient.

There is continued interest in developing more stable contacts to a variety of GaN-based devices. In this paper we give two examples of devices that show improved thermal stability when boride, nitride or Ir diffusion barriers are employed in Ohmic contact stacks. AlGaN/GaN High Electron Mobility Transistors (HEMTs) were fabricated with Ti/Al/X /Ti/Au source/
drain Ohmic (where X is TiB2, ZrN, TiN, TaN or Ir) contacts and subjected to long-term annealing at 350°C. For GaN layers with an electron concentration of ∼3×1017 cm-3, the minimum specific contact resistance achieved is 6×10-5 Ω cm2 for Ti/Al/TiN/Ti/Au after annealing at 800°C. The specific contact resistance was found to strongly depend on the doping level, suggesting that tunneling is the dominant mechanism of current flow. By comparison with companion devices with conventional Ti/Al/Ni/Au Ohmic contacts, the HEMTs with boride-based Ohmic metal showed superior stability of both source-drain current and transconductance after 25 days aging at 350°C. The gate current for standard HEMTs increases during aging and the standard Ohmic contacts eventually fail by shorting to the gate contact. Similarly, InGaN/GaN multiple quantum well light-emitting diodes (MQW-LEDs) were fabricated with either Ni/Au/TiB2/Ti/Au or Ni/Au/Ir/Au p-Ohmic contacts. Both of these contacts showed superior long-term thermal stability compared to LEDs with conventional Ni/Au contacts.

The development of reliable and thermally stable Ohmic and Schottky contacts to ZnO is one of the critical issues related to the fabrication of ZnO-based UV light emitters/detectors and field effect transistors. To date, a number of different metallization schemes and surface cleaning procedures prior to metal deposition have been examined for rectifying contacts on n-ZnO. While these reports have shown that low reactive metals such as Au, Ag and Pd form rectifying contacts with Schottky barrier heights in the 0.6-0.8 eV range, the thermal stability of these contacts is usually extremely poor, with degradation occurring even at 60°C for Au/n-ZnO. One approach to achieving increased barrier heights that has proven successful for GaAs, InP, InGaAs and other compound semiconductors is the use of cryogenic deposition temperatures. In this context, we report in this work on the effect of cryogenic temperature metal deposition on the contact properties of Pd, Pt, Ti, and Ni on single-crystal n-type ZnO. Deposition at both room and low temperature produced contacts with Ohmic characteristics for Ti and Ni metallizations. In comparison, both Pd and Pt contacts showed rectifying characteristics after deposition. All rectifying contacts exhibited barrier heights around 1-2 eV and idealities between 1 and 2. Low temperature deposition gave higher resistances in comparison to room temperature deposition for all cases. Larger contacts also corresponded to an increase in resistance. Changes in contact behavior were measured on Pd to anneal temperatures of ∼300°C, showing an increase in barrier height along with a decrease in ideality with increasing temperature. This difference with annealing temperature is in sharp contrast to previous results for Au contacts to ZnO. There were no differences in near-surface stoichiometry for the different deposition temperatures; however low temperature contacts demonstrated some cracking in Pt and Pd, probably due to surface stress.

The survival of patients with head and neck squamous cell carcinoma has changed little over the last 30 years. However, with recent advances in the fields of cellular and molecular immunology, there is renewed optimism with regards to the development of novel methods of early diagnosis, prognosis estimation and treatment improvement for patients with head and neck squamous cell carcinoma. Here, we present a critical review of the recent advances in tumour immunology, and of the current efforts to apply new immunotherapeutic techniques in the treatment of head and neck squamous cell carcinoma.

An understanding of the immune system and its modes of action is fundamental to understanding the causes, natural history, management and treatment of many diseases. As such, a grasp of the principles of immunology is essential for every physician.

This paper represents a succinct overview of the immune system, discussing the major components in turn, in respect of structure, function and integrated organisation, in relation to head and neck cancer.

The outcome for patients with head and neck squamous cell carcinoma remains poor, despite improvements in diagnosis and treatment over the past three decades. This has triggered great interest in the genetic events that underpin the aetiology and clinical behaviour of this group of cancers. As a result, the genetic profile for head and neck squamous cell carcinomas at different sub-sites has been relatively well characterised at the chromosomal level. Various studies have shown links between specific aberrations in head and neck squamous cell carcinoma and clinical outcome, e.g. loss of heterozygosity at 2q and 18q is commonly associated with poor prognosis, and loss of heterozygosity at 9p21 is associated with recurrence. However, there is as yet no significant clinical application of this genetic knowledge as regards the screening, diagnosis or treatment of head and neck squamous cell carcinoma. Here, we summarise the current state of knowledge, and highlight the most promising areas of research that may facilitate the translation of genetic data into clinical benefit.

Occupational rhinitis has been a prescribed industrial disease in the UK since 1907. It has only relatively recently received significant attention from otorhinolaryngologists although numerous studies have been performed in the past by occupational and industrial health physicians. At the present time the precise mechanisms of pathogenesis are unclear and would appear to be multiple.

Recently interest has arisen because of compensation claims. Diagnosis made on the basis of the clinical history is subject to two problems: firstly, there is difficulty in differentiating between occupational and nonoccupational rhinitis, and secondly, clinical histories can easily be feigned. Physical signs would be a more reliable indicator of occupational damage to the nasal mucosa if they differ from the signs normally found in allergic or vasomotor rhinitis. In a series of 100 shipyard workers dry atrophic nasal mucosa was found in 66and septal ulceration in two. From their clinical histories 78 individuals complained of nasal obstruction, 28 of epistaxis, 42 of hyposmia, 10 of anosmia and 90 of rhinorrhoea. Possible pathogenesis is described

Acyclovir is a specific anti-viral agent which has been used in the treatment of the Ramsay Hunt Syndrome with encouraging results. To our knowledge, no previous study has been published utilizing this treatment. A discussion is also undertaken of the underlying pathology and prognosis of the Ramsay Hunt Syndrome, with a summary of those cases in which Acyclovir was prescribed.